Centrifugal pump



Sept'. 3, 1935.

s. E. sLocuM CENTRIFUGAL PUMP Filed March 16, 1955 Y 2 Sheets-Sheerl 1 Sept 3; 1935-n s. E. sLcuM 1 2,013,078

CENTRIFUGAL PUMP Filed March 16. 1933 2 Sheets-Sheet 42 Patented Sept. 3, 1935 UNITED STATES PATENT ori-ica This invention in general relates to a means for improving the performance of centrifugal pumps. p

One object of the invention is to provide means for preventing retrograde movement of the fluid at the tips of the blades in a centrifugal pump of the propeller type.

Another object of the invention is to provide a centrifugal pump in which there is a two-stage handling of the fluid passing through the pump, the primary stage having a. propeller for directin thev ilud to the secondary stage, the tips of 'the propeller being set into a. recess in the casing to impede retrograde movement of the uid around them, the secondary stage having an impeller which expels the fluid at right angles centrifugally into the discharge passage.

Infthe drawings:

i Figure 1 is .a central longitudinal section through the centrifugal pump of my invention.

Figure 2 is a central longitudinal section through a modied form of pump with exterior bearinga'taken along the line 2 2 of Figure 3.

Figure 3 is a transverse section along the line 3-3 of Figure 2.

Referring to the drawings in detail, I is a base upon the right-hand end of which is mounted a ball bearing 3 in the housing t mounted by the bolts 5 upon the base brackets 6.

'I'his base is provided with a bracket 'I for supporting the volute delivery chamber wall 3, which chamber progressively increases vin diameter towards the outlet. This progressively increasing volute lspace I0 communicates by a passageway II with the peripheral outlets I2 of the centrifugalimpeller I3 which is supported by the bearsing members I4 and I5 on either side.

The bearing member I4 rests within the wall I6 which forms one side of a pump casing and is an exten-y sion of the volute chamber wall 3. Bolted to the volutev chamber wall 8 is the wall I'I of an intermediate casing whichforms the other side of the pump casing and supports the bearing I5.

The intermediate casing has 'converging coneshaped walls I8 forming a, Venturi inlet passageway I3l that communicate with the radial passageways 20 of the impeller I3. 4The impeller 1 I3 has a hub2I mounted upon thev shaft 22 which is supported in the bearing 3 and is driven by the coupling 2b. Mountedl lon this shaft and engaging with the propeller hub 2| is a polished bronze sleeve 24 having rubber gaskets 25g at either end. At the left hand end'of vthis sleeve 24 is mounted the hub 25 of a propeller having the buckets or blades 26, the rounded ends of lcasing l'and bearing I4.

which fit within correspondingly rounded recesses 21 at the entrance to the venturi I8 so asto impede retrograde movement of the flui around the tips of the blades.

Bolted to the intermediate casing l'I is an inlet casing 29 having large inlet passageways 33 through which incoming fluid ows over the bronze sleeve 3i abutting the hub 33v of the propeller 26.

This bronze sleeve extends along the shaft 22 and is held in position at its left hand end by the nut 32 and screw 33'which is threaded inte the end of the shaft 22j The nut 32 is threadei upon the end of the shaftand also engages vwith the end of the bronze sleeve 3i. This bronze sleeve 3l is mounted vin a marine type cutless rubber bearing sleeve 34 held vbetween the end of the inlet casing 29 and the 'end of the shaft. Aroundthis rubber bearing is a bronze sleeve 35 mounted within the sleeve 36 of a cast iron bearing casing 3l bolted by the bolts 33on the left hand` end of the inlet casing 29. Water passageways 33 provide for the circulation of water to cool and lubricate the bearing. This passage- Way communicates with the. chamber til formed within the closed left hand end of the .bearing casing 3l.

Itlwill be noted that the casing 23 is attached to the casing 'Il by the bolts 29a and the bolts 8L attach the casing I'I to the volute casing 3 and I6. The volute casing is provided'with a Water passageway 4I controlled by the valve 32 for applying water to theV bearing 43 carried within the sleeve 44. A nut 45 retains the bearing 33 and its packing in positionY by the packing gland 46. This structureV is mountedy around the hollow `sleeve 4l which is an extension of the impeller hub 2l and is hollow for the circulation of air in' order to maintain the bearing in cooled condition.

In order to prevent the shaft 22 from moving laterally the bearing 3 has its inner portion set between the shoulders 3 and 3b screwed on the shaft. The outer portion is carried between the bearing casing ends t'. which are, in turn attached by the bolts 5 to the foundation brackets 6 so that there can be no lateral shifting of the shaft.

' Byk tightening the screw 33 the entire sleeve systeni comprising the sleeves 3I, hub 25, sleeve 24 and hub 2| are held tightly against the volute As the casing I6 is mounted on the bracket, it is thus ,seen`that the entire pump is held together on a common base I without lost motion or wearancl can be adl tions and uses.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

In a pump, a pump casing having in one side bearings and on its op'posite side abone-shaped wall forming a Venturi inlet, an impeller in the f casing having' a hollow sleeve mounted in the bearings,v a shaft (for the lmpeller projecting throughv the inlet. a propeller on the shaft, a sleeve on the shaft between the impeller and propeller, a second sleeve on the shaft' to urge the propeller against the first-named sleeve, and a bearing to support the second sleeve for rotation, said propeller comprising propeller blades having rounded ends, said venturi having an entrance opening and a rounded recess of greater diameter than said opening adjacent thereto into which the rounded ends of said propeller blades t, whereby to prevent retrograde movement of the fluid moved by said propeller blades through said Venturi inlet.

STEPHEN E. SLOCUM. 

